You will never see the great auk, the laughing owl, or the O’ahu ‘O’o at the zoo or even in the wild because these species are gone forever. That's extinction—when all the members of a species have died. Once a species becomes extinct, our planet changes forever.

Extinction is a natural part of our Earth’s history, but today species are becoming extinct faster than ever. Every year, new species are becoming threatened with extinction.

When a species is endangered, scientists monitor it closely year after year. Accurate information about population size and distribution helps scientists plan conservation efforts and identify areas where the species is in most danger. Then they can take action before it’s too late.

The Pipefish and the Seahorse

In 1994, a South African river pipefish was listed as extinct. But one year later, a healthy new population was discovered. This second chance to save the pipefish might have been lost if scientists hadn’t monitored local species.

Some species of seahorse, close relatives of the pipefish, are also under threat. Large numbers are taken from the wild and sold for home aquariums. Seahorses also live in threatened marine habitats, like coral reefs. By tracking seahorse populations, scientists can trace these problems and find solutions. Now they’re working with fishermen to set up seahorse sanctuaries.